Thursday, August 23, 2012
Monday, August 20, 2012
Sunday, August 19, 2012
Tuesday, August 14, 2012
Deformation of EM wave signals
Deformation of EM wave signals
14 August 2012
Electromagnetic wave carries signals emitted
by antenna into space. The EM field of a wave is mathematically defined by the
EM wave equation whose monochromatic solution is the equation (1). A signal is a time varying EM field that can be expressed
by Fourier series which is the sum of monochromatic wave functions, that is, a
sum of equation (1) of different amplitudes and wave lengths.
We notice that the amplitude and phase of the
equation (1) vary with distance and frequency, that is, monochromatic
EM waves of different frequencies evolve differently in space. In consequence,
the form of the Fourier series is distorted, the traveling signal is deformed.
What is the extent of the deformation of EM signal in space?
Please read the following document
Used documents links
Why EM wave equation does not conform to relativity? http://pengkuanem.blogspot.com/2012/08/why-em-wave-equation-does-not-conform.html
Wednesday, August 1, 2012
Why EM wave equation does not conform to relativity?
Why EM wave equation does not conform to relativity?
1 August 2012
This question is not about real electromagnetic
wave. Physical wave does not violate relativity principle and always travel at
constant speed c. It is the electromagnetic wave equation that does not conform
to relativity. By computing the speed of the solution of the wave equation, we
find that its velocity is faster than that of light and varies with distance
and frequency. This result proves that the wave equation does not faithfully describe
the physical phenomenon of electromagnetic wave.
A rigorous mathematical proof is given
below. The annex is provided just in case where someone wants to check the
validity of the used equations and is not necessary to the proof.
We study the spherical wave sent by an element of antenna of length dl which carries a current I (see the Figure 1). As the magnetic field of this element is only in the phi direction, in spherical coordinates, the general wave equation simplifies to the polar wave equation for the phi component. The polar wave equation admits the an analytical solution (ref. Clayton R. Paul, Keith W. Whites and Syed A. Nasar, Introduction to Electromagnetic Fields, Mcgraw-Hill College; 3 Sub edition (December 9, 1997), p.590). We call this solution “antenna wave”.
Please read the following document
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